The invention relates to a printing system for printing a plurality of images on a web, the printing system comprising a print engine, a feeder for feeding the web to the print engine in a feed direction relative said print engine, a receiver for receiving the printed web, a user interface configured to set a printing arrangement of the plurality of images on the web and to input the print engine, the feeder and the receiver for performing printing according to the printing arrangement by ejecting or adhering marking material on the web; and a scheduling module for scheduling the plurality of images on the web. The printing system may be an inkjet printing system or a toner printing system.
Printing systems for printing a plurality of images on a web are known in the art. The printing systems comprise a print engine and feed means for feeding the web to the print engine in a feed direction. The printing systems also comprise a user interface that allows an operator to arrange the plurality of figures in a printing arrangement. The printing arrangement comprises a print queue of digital images to be printed. In the printing arrangement the images of said plurality are arranged adjacent to each other along the feed direction on the web to set printing. In general, the printing arrangement can be seen in a display screen of the user interface. Then, said user interface inputs the print engine and the feed means to perform printing on the web according to the printing arrangement as said web is leaded to the print engine.
Usually the web is extracted from an input roll which is loaded in an input module of the printing system. In order to save web, the plurality of images are usually arranged on the web close to each other along the feed direction. The print engine is configured to eject marking material like ink or toner on the web according to the printing arrangement. The images to be printed are distributed along the web. While the images scheduled for the web are printed by means of the marking material ejection on the web, the web is received by a receiving module of the printing system in order to establish an output roll in case the receiving module is an output roll module or cut sheets in case the receiver is a cutter. A core of the input roll and a core of the output roll may be loaded in the input roll module and in the receiving module respectively. In case of post-processing of the output roll, it is desired that the post-processing steps can be executed without loss of a print quality of the end product.
Receiving material is also referring to as “media” or “print media” in this description of the patent application.
A first problem with respect to the print quality of images printed from an input roll is the well-known print curl effect. A consequence of a print curl effect may be a finishing problem in a finisher which is intended to post-process a printed web, for example a laminating device. The print curl effect may cause a paper jam in the finisher or print quality issues during a finishing step of the finisher. For example, bubbling issues or orange peel issues may be generated during lamination.
A second problem with respect to the print quality of images printed from an input roll is that the receiving material is cambered when approaching the end of the input roll. When the receiving material is not completely flat on a print surface, paper step errors, bi-directional errors and banding errors may occur. This may especially impact an image with a high-density coverage or for a print mode where a ratio of quality versus production is hardest to be achieved. Typically is a production print mode for which the operator expects a good enough quality, but at a high speed. Also a presence within margins of areas of an image of certain flat colors make the image more subject to banding print artifacts. The camber of the receiving material may depend on a media type and even on a history of the input roll. A roll which suffered humidity or temperature changes may have a longer, stiffer cambered part than when the roll is new.
In general, images are printed on the web in an order of arrival at the controller of the printing system. Some images may involve a higher risk of finishing quality if they are located in the first part of the input roll—the starting point of printing on the web—and/or on the last part of the input roll—the ending point of printing on the web.
It is an object of the present invention to use a maximum of the receiving material when printing and not to be forced to throw away a first or last part of the web due to risks on print quality.